You can get very stiff fabric by mixing your own starch and it would probably cost less
than Sta-Flo. We don't have Sta-Flo here so I mix my own starch and cook it for a minute
to stabilize it. I mix 1/4 cup of cornstarch with 1/2 cup of cold water then add 1 quart of
boiling water. Stir it well and bring to a boil for a min. Let cool.
Sometimes I add more water if I don't want it as stiff as cardboard. Hope this helps.